The effect of hydra peptide morphogen on the levels of beta-endorphin and some blood and adrenal hormones in albino rats]

The influence of PMH on the level of beta-endorphin and some hormones of blood and adrenal glands was studied. The dose A (10 mkg/kg) and dose W (100 mkg/kg) of PMH were used in our experiments. Earlier it has been discovered, that PMH in such doses stimulated the processes of cell division in 24 hours since the moment of injection. The stimulation was dose-dependent. Within 24 hours PMH in A dose decreased the concentration of beta-endorphin in the blood 2.7-fold, ad in dose W increased it 2 times. The level of corticosterone in blood and adrenal glands after the injection of PMH in dose A exceeded the control data trustworthy in 4 and 24 hours since the moment of injection. In dose B in 4 hours 1.5-fold reduction of corticosterone concentration took place in the blood. Increase in epinephrine level in adrenal glands was observed after PMH administration in two doses. Content of T3 increased in 4 hours after PMH injection in dose B. The role of hormonal changes in stimulating cell division accompanied by PMH injection is discussed. The data received show that PMH influences directly proliferative processes.     

Participation of peptide hydra morphogen in the regulation of proliferation processes in different tissues of white rats]

The PMH influence on proliferation processes in some tissues of white rats was studied. PMH injections in doses 10.0 mkg/kg and 100.0 mkg/kg stimulated the processes of DNA--synthesis after 24 hours in corneal and tongue epithelium. The direct dose-dependent effect was revealed. PMH in dose 10.0 mkg/kg activated the proliferative processes in the stomach epithelium and thymus cortex. after 24 hours too. The given dose of PMH caused trustworthy decreasing of proliferative activity in thymus after 4 hours. The stimulation of DNA-synthesis and acceleration of mitosis were found after 5-times application on white rat's corneal with 100 nM PMH solution.     

LPS/D-GalN诱导小鼠急性肝损伤模型的建立

目的建立脂多糖(lipopolysaccharide,LPS)/D-氨基半乳糖(D-galactosamine,D-GalN)诱导小鼠急性肝损伤模型。方法 40只雌性C57BL/6小鼠用于观察8种不同LPS与D-GalN剂量配比联合刺激后小鼠存活时间,以确定模型建立的最佳剂量。使用腹腔注射最佳剂量染毒32只雌性C57BL/6小鼠,分别在0、1、4、8 h处死,每组8只,0 h注射相同剂量生理盐水作为对照。观察染毒后小鼠肝组织病理损伤,检测血清中ALT及炎症因子IL-6、MCP-1和TNF-α表达水平变化。结果通过观察小鼠存活时间,确定腹腔注射最佳染毒剂量为LPS(2.5 mg/kg)/D-GalN(0.3 g/kg);小鼠染毒后肝组织呈进程性病变,最终发展为肝脏弥漫性坏死,肝细胞核崩解。与对照组相比,血清ALT显著升高(P0.001),IL-6、MCP-1、TNF-α均在1 h后达到最高水平(P0.001),然后持续下降。结论成功建立LPS/D-GaIN诱导小鼠急性肝损伤模型,为探索急性肝损伤的致病机制以及药物干预治疗提供有效的动物模型。     

ICV injection of orexin A induces synthesis of total RNA and mRNA encoding preorexin in various cerebral regions of the rat

This experiment evaluated the induction of RNA synthesis in neurons of various cerebral areas during hyperthermia induced by an intracerebroventricular injection of orexin A. The firing rates of the sympathetic nerves to interscapular brown adipose tissue, along with interscapular brown adipose tissue and colon temperatures, and heart rate were monitored in urethane-anesthetized male Sprague–Dawley rats before and after an injection of orexin A (1.5 nmol) into the lateral cerebral ventricle. Furthermore, the incorporation of ³H-uridine in total RNA and the expression of mRNA encoding the precursor of orexin A were measured in the cerebral areas at the 4th hour after the injection. The same variables were monitored in control rats with an injection of saline. The results show that orexin A increases the sympathetic firing rate, interscapular brown adipose tissue and colonic temperatures, heart rate, along with: (1) the incorporation of ³H-uridine in total RNA of the hypothalamus, hippocampus, cortex and cerebellum, (2) the expression of mRNA encoding the precursor of orexin A in the hypothalamus, cortex and cerebellum. These findings indicate that orexin A induces polyhedral gene expressions in several cerebral regions. Furthermore, we insist to suggest the name “hyperthermine A” as an additional denomination of “orexin A” by considering the strong influence of this neuropeptide on body temperature.     

Endotoxin administration increases hypothalamic somatostatin mRNA through nitric oxide release

Acute inflammation induced by endotoxin (LPS) administration inhibits insulin-like growth factor (IGF-I) and growth hormone (GH) secretion. The aim of this study was to elucidate the role of glucocorticoids and nitric oxide (NO) in the effect of LPS on hypothalamic somatostatin gene expression. Adult male Wistar rats were injected with different doses of LPS (5, 10 and 100 microg/kg). Rats received two i.p. injections of LPS (at 17:30 and 8:30 h the following day) and were killed 4 h after the second injection. LPS administration at the dose of 100 microg/kg increased the hypothalamic somatostatin mRNA content, as well as the serum concentrations of corticosterone. Glucocorticoids do not seem to be involved in LPS-induced increase in hypothalamic somatostatin mRNA since adrenalectomy did not prevent this effect. In order to analyze the possible effect of NO, aminoguanidine, an inducible nitric oxide synthase inhibitor, was injected (100 mg/kg s.c.) simultaneously with LPS injection. Aminoguanidine administration did not modify somatostatin mRNA in saline injected rats, but it prevented LPS-induced increase in hypothalamic somatostatin mRNA. These data suggest that the stimulatory effect of endotoxin on hypothalamic somatostatin gene expression is not mediated by glucocorticoids, but instead by the increase in NO release.     

Effect of ergotoxin on gastric motility in the skate, frog and turtle

DG-erotoxine (SPOFA)--200 mg/kh b. w. has no effect to the motor activity in scates. The dose of 500 mkg/kh produces 20-30 min. after injection the excitation of contraction followed by the inhibition. In frogs the dose of 25 mkg/kg produces the excitation of stomach contractions. The dose of 100 mkg/kg initially stimulates motor activity, later on--inhibits it. In the tortoise the dose of 25 mkg/kg increases the contraction of the stomach the dose of 2000 mkg/kg inhibits it.     

Gene expression-based detection of radiation exposure in mice after treatment with granulocyte colony-stimulating factor and lipopolysaccharide

In a large-scale nuclear incident, many thousands of people may be exposed to a wide range of radiation doses. Rapid biological dosimetry will be required on an individualized basis to estimate the exposures and to make treatment decisions. To ameliorate the adverse effects of exposure, victims may be treated with one or more cytokine growth factors, including granulocyte colony-stimulating factor (G-CSF), which has therapeutic efficacy for treating radiation-induced bone marrow ablation by stimulating granulopoiesis. The existence of infections and the administration of G-CSF each may confound the ability to achieve reliable dosimetry by gene expression analysis. In this study, C57BL/6 mice were used to determine the extent to which G-CSF and lipopolysaccharide (LPS, which simulates infection by gram-negative bacteria) alter the expression of genes that are either radiation-responsive or non-responsive, i.e., show potential for use as endogenous controls. Mice were acutely exposed to (60)Co γ rays at either 0 Gy or 6 Gy. Two hours later the animals were injected with either 0.1 mg/kg of G-CSF or 0.3 mg/kg of LPS. Expression levels of 96 different gene targets were evaluated in peripheral blood after an additional 4 or 24 h using real-time quantitative PCR. The results indicate that the expression levels of some genes are altered by LPS, but altered expression after G-CSF treatment was generally not observed. The expression levels of many genes therefore retain utility for biological dosimetry or as endogenous controls. These data suggest that PCR-based quantitative gene expression analyses may have utility in radiation biodosimetry in humans even in the presence of an infection or after treatment with G-CSF.     

Differential regulation of vasopressin gene expression in the hypothalamus of endotoxin-treated 14-day-old rat.

The E. coli endotoxin 0111 B4, a lipopolysaccharide (LPS), in a dose of 200 ng/kg body weight/50 microl artificial cerebrospinal fluid (CSF) was given intracisternally to 14-day-old rats. Four hours later CSF, blood and urine were sampled, and consecutive brain sections from the hypothalamic area of the brain were prepared for in situ hybridization. The LPS treatment resulted in a significant (p<0.001) pleocytosis and an elevation of the protein content of the CSF. There were no changes observed in the chemical parameters of the CSF, plasma, blood or urine, i.e. vasopressin (VP) levels, osmolality, Na+ and K+ concentrations, glucose level, pH, bicarbonate or PaCO2, PaO2 values. LPS injection, however, resulted in a significantly (p<0.01) increased VP mRNA level (121% of the control value) in the supraoptic nuclei (SON), but not in the paraventricular nuclei (PVN), as compared to controls. Our findings suggest an early effect of LPS on VP gene expression selectively in the SON of 14-days-old rats. This animal model might be suitable for studying the regulation of VP gene expression and the role of this peptide in the pathogenesis of bacterial meningitis in pediatric patients.     

Effects of different serotypes of Escherichia coli lipopolysaccharides on body temperature in rats

The effects of Escherichia coli O55:B5, O127:B8, and O111:B4 serotypes' lipopolysaccharides (LPS) on body temperature were investigated in rats. LPSs were injected intraperitoneally at doses of 2, 50, and 250 microg/kg. A multiphasic and no-dose dependent increase in rectal temperature was observed in response to E. coli O55:B5 LPS at all doses, and in response to E. coli O127:B8 LPS at 2 and 50 microg/kg doses. The highest dose of the latter caused a dual change in rectal temperature, in which hypothermia preceded fever. E. coli O111:B4 LPS was either pyrogenic or hypothermic at 2 and 250 microg/kg doses; respectively, whereas a dual response was observed when the 50 microg/kg dose was injected. Although dual responses were observed after administration of all LPSs at 50 microg/kg dose when the body temperature was recorded by biotelemetry, the hypothermia induced by E. coli O55:B5 LPS was significantly smaller. These data suggest that LPSs induce dose and serotype-specific variable changes on body temperature in rats. This variability may be related to the structure of LPSs. The data also indicate that LPS causes hypothermia with or without fever in rats.     

Tolerance to low-dose endotoxin in awake sheep

Dose response and tolerance to a small intravenous dose of Serratia marcescens lipopolysaccharide (LPS) were studied in awake sheep. Core temperature significantly increased after a dose of 0.002 micrograms/kg; changes in pulmonary arterial pressure, pulmonary vascular resistance, plasma thromboxane B2, and circulating leukocyte concentration occurred after 0.02 micrograms/kg; plasma 6-keto-prostaglandin F1 alpha increased after 0.2 micrograms/kg. Development of acute tolerance was studied by injection of S. marcescens LPS (0.02 micrograms/kg iv) on 3 consecutive days: pulmonary arterial pressure and thromboxane B2 levels were significantly lower than controls after the second dose, whereas fever and the degree of leukopenia were not diminished until the third dose. After intravenous administration of LPS given in increasing doses from 0.1 to 3.2 micrograms/kg three times weekly over 7 wk, there were no measurable changes in any of the above parameters after challenge with S. marcescens LPS (0.02 micrograms/kg) after a 1-wk rest period. In awake sheep, small intravenous doses of LPS can cause physiologically important changes of the pulmonary circulation and can alter the hemodynamic and eicosanoid mediator responses to subsequent challenges with LPS. Large intravenous doses of LPS can ablate the physiological responses to subsequent small doses of LPS.     

Time course of anterior pituitary estrogen receptor after low 17 beta-estradiol doses in ovariectomized rats

The present paper describes the effect of three 17-beta-estradiol (E2) doses (1, 10 and 500 ng E2/kg) on the cytosolic and nuclear estrogen receptor content of anterior pituitary (Ap) of ovariectomized rats. The estrogen receptors were measured by [3H]E2 exchange in cytosol and crude nuclear fractions. Two hours after the administration of 10 or 500 ng E2/kg the Rc showed a depletion to 20-30% of preinjection level. The 1 ng E2/kg dose did not provoke any Rc depletion. The Rc replenishment was completed 5 h after injection of 10 ng E2/kg, but it was delayed to 10 h after injection of 500 ng E2/kg. An increased amount of Rc over the control levels was produced by 1 and 10 ng E2/kg doses, but not by the 500 ng E2/kg. The Rn level in Ap increased significantly after all E2 doses, and their highest levels were similar for 1, 10 and 500 ng E2/kg. These results suggest that some estrogenic responses like synthesis of the estrogen receptor proteins, can be elicited without previous significant Rc depletion. The relationships between Rc and Rn in Ap suggest an autoregulatory mechanism for the control of the cellular level of unbound estrogen receptors, that can be altered by the exogenous E2.     

SB-334867 (an Orexin-1 Receptor Antagonist) Effects on Morphine-Induced Sensitization in Mice—a View on Receptor Mechanisms

The present study focused upon the role of SB-334867, an orexin-1 receptor antagonist, in the acquisition of morphine-induced sensitization to locomotor activity in mice. Behavioral sensitization is an enhanced systemic reaction to the same dose of an addictive substance, which assumingly increases both the desire for the drug and the risk of relapse to addiction. Morphine-induced sensitization in mice was achieved by sporadic doses (five injections every 3 days) of morphine (10 mg/kg, i.p.), while a challenge dose of morphine (10 mg/kg) was injected 7 days later. In order to assess the impact of orexin system blockade on the acquisition of sensitization, SB-334867 was administered before each morphine injection, except the morphine challenge dose. The locomotor activity test was performed on each day of morphine administration. Brain structures (striatum, hippocampus, and prefrontal cortex) were collected after behavioral tests for molecular experiments in which mRNA expression of orexin, dopamine, and adenosine receptors was explored by the qRT-PCR technique. Additionally, the mRNA expression of markers, such as GFAP and Iba-1, was also analyzed by the same technique. SB-334867 inhibited the acquisition of morphine-induced sensitization to locomotor activity of mice. Significant alterations were observed in mRNA expression of orexin, dopamine, and adenosine receptors and in the expression of GFAP and Iba-1, showing a broad range of interactions in the mesolimbic system among orexin, dopamine, adenosine, and glial cells during behavioral sensitization. Summing up, the orexin system may be an effective measure to inhibit morphine-induced behavioral sensitization.     

Effect of testosterone on carboxypeptidase H activity in the murine hypothalamus and hypophysis

Effects of single intraperitoneal administration of testosterone propionate (3 or 30 mg/kg body weight) on activity of carboxypeptidase H in pituitary body and hypothalamus of female white mouse were studied. It was found that testosterone propionate treatment (3 and 30 mg/kg body weight) increased the carboxypeptidase H activity in pituitary through 0.5 hour and it decreased one in 24 hours after treatment. The carboxypeptidase H activity in hypothalamus was lower as compared with control animals in 24 hours after testosterone propionate treatment in the dose 3 mg/kg body weight. However, the carboxypeptidase H activity in hypothalamus was lower in 0.5 and 24 hours and it was higher in 4 h after testosterone propionate treatment in the dose 30 mg/kg body weight as compared with the control. These data suggest that testosterone affects the carboxypeptidase H activity by changing the level of enzyme gene expression.     

CFTR基因在小鼠肠道组织中的差异表达

目的研究肠道组织CFTR基因表达与分泌性腹泻发生的关系。方法选取KM小鼠24只,雌雄各半,随机分为3组（每组8只）：对照组经小鼠腹腔注射0.2 mL生理盐水,实验组小鼠经腹腔注射LPS[6 mg/（kg·bw）]分别作用1 h、8 h,于注射后通过小鼠精神状态、肠道组织形态学判定分泌性腹泻模型的建立,利用荧光定量PCR法检测各段肠道组织CFTR基因的表达。结果 LPS成功诱导小鼠发生了分泌性腹泻;CFTR基因在小鼠十二指肠、空肠、回肠和结肠组织中均有不同的表达丰度,以结肠最高,但各段肠道间差异不显著;与对照组相比,LPS上调了十二指肠、空肠和回肠CFTR基因的转录,下调了结肠CFTR基因的转录。结论提示肠道组织CFTR基因转录水平的上调与LPS诱导分泌性腹泻的发生密切相关,且在各肠段发挥的作用不同,其中空肠在氯离子（Cl-）分泌中发挥主要作用,结肠的作用最弱。     

急性肺损伤大鼠肺组织TOLL样受体4及CD14mRNA的表达

目的 探讨内毒素致急性肺损伤大鼠肺组织TOLL样受体4及CD14 mRNA表达的变化.方法 24只雄性Wistar大鼠随机分为2组:对照组、LPS模型组,每组再分为4 h和8 h两个亚组.尾静脉注射脂多糖(LPS)(10 mg/kg)建立大鼠急性肺损伤模型.检测大鼠动脉血气、肺体指数,实时荧光定量PCR测定肺组织TOLL样受体4及CD14 mRNA的表达,并观察肺组织病理变化.结果 与对照组相比,模型组4 h和8 h时大鼠肺组织中的TLR4及CD14 mRNA表达均显著增高(P＜0.05或P＜0.01).病理学观察显示,模型组大鼠肺组织出现出血及坏死.结论 内毒素致急性肺损伤的发病机制可能与TLR4及CD14 mRNA的表达升高有关.     

Expression of oncogenes in the rat liver under conditions of template biosynthesis uncoupling by sublethal doses of cycloheximide

Injection of sublethal doses of cycloheximide (CHI) to rats allowed to reveal three stages in the dynamics of protein synthesis: 1) suppression stage (0-6 hrs), 2) regeneration stage (6-12 hrs), 3) stimulation stage (6-12 hrs). RNA-polymerases are activated when protein synthesis is inhibited. The stimulation stage precedes the activation of DNA replication. This model of DNA replication induced by CHI is specified by the expression of various cell oncogenes (c-fos, c-mys, p53, c-Ha-ras, c-sis, c-src). The investigated oncogenes may be divided into 4 groups according to the character of their expression. 1. Oncogenes (c-fos, c-myc) are switched on step-by-step 1 hour after CHI injection, the superexpression of the oncogenes being comparatively short. Maximum expression of c-fos and c-myc oncogenes is registered after 2-3 hours, respectively. 2./p53 oncogene expression increases within a few hours' after CHI injection and manifests itself at all three stages of protein synthesis till DNA replication. 3. c-Ha-ras oncogene is expressed at a high level in control and experimental animals. 4. Expression of c-sis and c-src oncogenes are absent both before and after CHI injection. Sublethal doses of CHI have the same effect on oncogene expression as the lethal ones.     

Spin trapping agent, phenyl N-tert-butylnitrone, reduces nitric oxide production in the rat brain during experimental meningitis

Phenyl N-tert-butylnitrone (PBN) is a spin trapping agent previously shown to exert a neuroprotective effect in infant rat brain during bacterial meningitis. In the present study, we investigated the effect of systemic PBN administration on nitric oxide (NO) production in a rat model of experimental meningitis induced by lipopolysaccharide (LPS). We assessed the NO concentration in rat brain tissues with an electron paramagnetic resonance (EPR) NO trapping technique. In this model, rats receiving intracisternal LPS administration showed symptoms of meningitis and cerebrospinal fluid (CSF) pleocytosis. The time course study indicated that the concentration of NO in the brain reached the maximum level 8.5h after injection of LPS, and returned to the control level 24 h after the injection. When various doses of PBN (125-400 mg/kg) were injected intraperitoneally 30 min prior to LPS, NO production in the brain was reduced with increasing PBN dose (250 mg/kg suppressed 80% at 8.5h after LPS injection), and white blood cells (WBC) in CSF were significantly decreased. We concluded that reduction of NO generation during bacterial meningitis contributes to the neuroprotective effect of PBN in addition to its possible direct scavenging of reactive oxygen intermediate (ROI).     

脂多糖对血管平滑肌细胞一氧化氮合酶基因表达及细胞增殖的影响

应用ＲＮＡ印迹分析和亚硝酸盐含量测定检查脂多糖（ＬＰＳ）对大鼠血管平滑肌细胞（ＶＳＭＣ）一氧化氮合酶（ＮＯＳ）基因表达及ＮＯ合成的影响,用３Ｈ－ＴｄＲ参入实验观察ＬＰＳ对细胞ＤＮＡ合成的影响．结果表明,ＬＰＳ在诱导ＶＳＭＣｉＮＯＳｍＲＮＡ表达和促进ＮＯ合成的同时,抑制ＶＳＭＣＤＮＡ合成．证明ＬＰＳ的作用与其浓度和作用时间有关     

A decrease in the acute toxicity of ethanol produced by zinc sulfate

It was shown that zinc sulphate injection during the acute alcohol intoxication resulted in the decrease of anaesthetic and toxic effects of ethanol. The most effective dose was 15 mkg/kg i.p. The possible mechanisms are discussed.     

The acute phase response in Japanese quail (Coturnix coturnix japonica)

Experiments were conducted to determine the effect of injection of lipopolysaccharide (LPS, from S. typhimurium) or muramyl dipeptide (MDP, N-acetylmuramyl-L-ala-isoglutamine) in Japanese quail. Doses of MDP between 0.3 and 10 mg/kg body wt. had no effect on body temperature. In contrast, doses of 1.0-22.5 mg LPS/kg body wt. caused significant increases in body temperature. None of the doses of LPS or MDP resulted in mortality. The febrile response to LPS was diminished following a second injection 48 h after the first, and was absent following a third injection. Plasma zinc, an indicator of the acute phase response, was significantly reduced by either LPS or MDP after the first injection (P<0.001), but not after the second or third injection. Splenic interleukin 1-beta (IL-1beta) mRNA expression was increased after the first and last injection of LPS (P<0.001), but only after the first injection of MDP (P<0.005). Hepatic IL-1beta mRNA expression was increased after the first, but not the third injection of LPS (P<0.001), while MDP had no effect. These data indicate that Japanese quail are less sensitive to MDP than LPS, and that quail demonstrate tolerance to LPS following repeated injections.